1. Technical Field
The present disclosure relates to a method of fabricating a non-volatile memory integrated circuit device and to a non-volatile memory integrated circuit device fabricated by using the method.
2. Description of the Related Art
Non-volatile memory integrated circuit devices can retain stored data even after the supply of power has been interrupted. As such, non-volatile memory integrated circuit devices are widely used in information communication devices, such as, for example, digital cameras, mobile phones, Personal Digital Assistants (PDA), or MPEG3 layer (MP3) players.
However, as information communication devices are moving more and more toward having expanded multi-functions, higher capacity and higher integration for non-volatile memory integrated circuit devices may now be required. Accordingly, the size of each memory cell constituting a non-volatile semiconductor integrated circuit device has rapidly decreased. With the decrease in the size of the memory cell, the width of a word line has also decreased, thereby increasing electrical resistance. The increased electrical resistance of the word line may also increase the resistance-capacitance (RC) delay of the word line in a read operation. As a result, the time required to read information from a selected cell, that is, the access time, may also increase. Therefore, to reduce the resistance of the word line, an attempt to form a word line as a dual-layer composed of a polysilicon pattern and a metal layer pattern has been made.